In U.S. Pat. Nos. 5,261,194, 5,329,737, and 5,560,151, a building structure is disclosed which is comprised of building blocks which are substantially triangular; the entire description of each of these United States patents is hereby incorporated by reference into this specification. This prior art building structure contains building blocks which require an independent key.
Furthermore, in this prior art structure, the key way, or recess, creates an undercut in the block which complicates its manufacture.
It is an object of this invention to provide a building block which can be more readily assembled than prior art building blocks.
It is another object of this invention to provide a building block which can be readily locked into tangential position of a radial structure upon assembly.
It is another object of this invention to provide a single type of building block which can be used variously for the construction of right circular cylinders, vaulted arches, straight vertical walls with vertical reinforcing ribs, and walls which are inclined slightly from the vertical, for use as a structural retaining wall.
It is another object of this invention to provide a novel interlocking radial structure which does not have an independent key and which can be made from a simple two piece mold without undercuts.